In industries concerned with subsurface operations in boreholes, there is often need for permanently or temporarily plugging off certain portions of a borehole system. One example relates to fracturing operations where a section of a borehole is isolated such that hydraulic pressure may be applied to that isolated area in order to fracture a formation surrounding the borehole in that location. For such operations it is common to land a plug on a seat in the borehole to effect the noted isolation. In some cases, seats for plugs are placed in the borehole at various times. Where these are placed prior to other operations or are left in place after the fracturing operation they may present an impediment to those other operations. Further, many prior art seat assemblies are complicated and dimensionally long. Accordingly, the art would well receive alternatives that overcome one or more of the foregoing drawbacks of the prior art.